Expansion-shield



E. W. MARSHALL.

EXPANSION SHIELD.

APPLICATION FILED AUG.15, I919.

. Patented Oct 25 and a resident of which is tures-thereof in appendedclaims.

tion is to provide a mm! W. umzut. or YONKERB, new YORK,

01 HOUNTAINVILLE, NEW YORK.

OFFICE.

ASSIGNOR r0 .1. Bowman oenzn,

EXPANSION-SHIELD.

To all whbm a Be it known that a citizen of the United States ofAmerica, Yonkers Westchester fork, have in- GOMGM I county, and State ofNew vented certain new and ments in Expansion-Shields, of which thefollowing is a specification, reference being.

liad to-the accompanying drawings, formin a part thereof. his inventionrelates to expansion shields and its objectis to provide a simple deviceinexpensive to manufacture and which may .be 'used to form an effectiveanchorage for bolts or screws in structures of cement, abrick, stone orother material with which the threads of the bolts or screws cannotobtain a good hold.

More specifically, the object of the invendevice of this character whichmay be made of sheet metal.

In order that my invention may,be thoroughl -understood, I will nowproceed to describe the same in the following specification and willthen point out the novel fea- Referring to the drawings:

' Flgure '1 is an elevation of a blank of shield made sheet metal withparts thereof cut away to form integral diagonal strips between the endsand edges of the blank.

F i 2 is an elevation .of an expansion shield made by rolling the blankof Fig. 1 into a tube.

Fig. 3 is asectional of. a wall or other structure having a hole thereinin which is inserted an expansion shield like that'shown in Fig. 2. Inthis figure a nut is shown in section and a bolt in elevation. g

4 is an elevation of a blank of sheet meta with a part thereofcorrugated and another part perforated to form oppositely inclineddiagonal strips.

Fig. 5 is an elevation of an expansion by rolling the blank of Fig.4into atube.

Fig. 6 is a sectional pansion shield like that shown in Fig. 5 in a holedrilled in a part of a wall.

Figs. 7 and 8 are portions of blanks having other forms of perforationswhich may be used either in tubes or sheets, to form shields which alsoembody this invention.

elevation of an ex- Specification of Letters Patent. Application filedAugust 15, 1919. BeriaI'No. 817,728.

, ERNEST W. MARSHALL,

useful Improve form and this will cause the strips to the shank of thebol elevation of a part 1s shown corrugated nected at their PatentedOct.

Fig. 9 is a perforated blank which may bedpressed or drawn into atubular shield an Fig. 10 is an elevation of a shield formed from theblank shown in Fig. 9'.

ike characters of referencg designate correspondlng parts in all the fires.

1O desi nates a rectangular lank of sheet metal. 11 Figs. 1, 2 forationsare punched through this blank intermediate its ends and ed es to formagonal ribs 11 connecting t e ends and This 'blank'is shown indesignates a structure in hole for this shown pushed ahead of the shield12. After as been done a bolt 22 which is drilled a clearance shield. InFig. 3 a nut 21 is into this hole, this h through theshield into' thenut.

It is-obvious that the nut may be drawn toward the [head of a latter andthat this will draw the strips 11 together, thus closing the spacesbetween them. This will cause an increase of the circumference andconsequently of the diameter of the part of the shield which'the stripsbe'disand outwardly against t and against the wall of the hole, and thusform a secure anchorage. It is to be noted that, this expansion willnnottake place along longitudinal lines but will be distributedcircumferentially thus gripping all partsof the circumference of thebolt and of the wall of the hole.

In Fig. .4 the lower part of the blank 10' at 13 for the purpose andforming screw threads when the blank is rolled into a tube 14 as shownin Fig. 5. Between this corrugated part of the blankand its upper endare angular perforations 15 so disposed as to leave a plurality ofdiagonal strips 16 inclined in one direction to the edges of the blankand to the axisof the tube 14, and a plurality of other diagonal strips17 inclined in another direction but at a greater angle to the edges ofthe block and to the axis of the tube. These strips when formed as thusdescribed, are intercom points of crossing.

. Fig.- 6 shows an expansion shield of this form inserted and expandedin a hole in the tortedboth inwardly and 3 slot-like per- Figs. 2 andbolt by turning the with a washer or other device 23 under its head, isput article held thereby against the side of the wall 20. The threads ofthe lag screw engage the threads formed by the corrugatlons which wouldotherwise be closed, cut off. Drawing the metal will change the shape ofthe perforations so that they will appear as they do in Fig. 10. Ofcourse other shapes '13 and when the screw is turned this end of ofperforations may be used. The lower end the shield is moved therebytoward the head of the bolt. This causes an increase of circumferenceand diameter of the part of the shield formed of the strips whichresults in the strips buckling or collapsing and forming an anchorage. 4Because of thefact that the ribs which run in one directlon are at agreater angle of inclination than those which run in the otherdirection, this expansion will be distributed circumferentially in orderto form a perfect anchorage by gripping all parts of the circumferenceof the lag screw and of the wall of the hole.

- The intermediate part of the blank may be formed as shown in Fig. 7with angular perforatiors 30, and 31 oppositely disposed or as shown inFig. 8 with angular perforations 32.

In both of these cases the rows of perforations are. inclined to thevertical edges of the blank. In the latter case the perforations 32increase in size toward the lower end of the blank which forms the innerend of the finished shield which 'will result in the first and greatestexpansion taking place at the inner end of the shield when it isshortened by longitudinal pressure.

It is obvious that a great variety of forms of perforations may be used,a few of which have been shown, and that these perforations may beeither formed in a tube or in a flat sheet which may be rolled into atube as described.

This invention is, I believe, capable of being carried out in manydifferent forms, some of which have been illustrated and described forthe purpose of showing structures which embody the invention, but I donot intend to limit myself to these specific forms of construction as itis well within the scope of the invention to manufacture expansionshields which embody this inwhich perforations 41 which in the blank arelonger circumferentially than they are radially. These perforations maybe disposed on curved lines such as A-B. This blank may be drawn into aseamless tube as shown at 42 In Fig. 10 with the upper end thereof,

ofthe tube is shown with helical corrugav tions rolled in it as at 43 toprovide screw threads for the reception of a screw or bolt.

What I claim is:

1. An ex ansion shield comprising a tubular member having between itsends a plurality of spaced straight parallel strips 1nclined to theraxisof the tube. 2. An ex ansion shield comprising a tubular mem er havingbetween its ends a plurality of oppositely inclined spaced diagonalstrips. F r

3. An ex ansion shield comprising a tubular member having between its.ends a plurality of oppositely inclined spaced interconnected diagonalstrips. p

4. An expansion shield comprising a tubular member having between itsends a plurality of oppositely inclined spaced interconnected diagonalstrips, the strips which are inclined in one direction 1 being at agreater angle to the axis of the tube than those which are inclined inthe opposite direction.

5.'An ex ansion shield com rising a tubular mem er, said member eingcorrugated near one of its ends to receive the threads of a bolt,said'member bein cut away at spaced intervals between the t readrece1ving means and its other end toform. a

plurality of strips inclined to the axis of the 6. An expansion shieldcomprising a tubular member, means near one end of said member forreceiving the threads of 'a bolt, said member being cut away at spacedintervals between the thread receiving means and its other end to formaplurality of oppositely inclined diagonal'strips.

An expansion shield comprising a tubular member, means near one end ofsaid member for receiving the threads of a bolt, said member being cutaway at spaced intervals between the thread receiving means and itsother end to form a plurality of oppositely inclined interconnecteddiagonal strips. I 8. An expansion shield comprising a tubular member,means near one end of said member for receiving the threads of a bolt,said member beingl cut away at spaced intervals between the t readreceiving means and its other end to form a plurality of oppositelyinclined interconnected diagonal strips, the strips which are inclinedin one direction bein at a greater angle to the axis of the tu e thanthose which are inclined in the opposite direction.

9. An expansion shield constructed of a h t metal blank perforated toform in the finished shield a plurality of oppositely inclinedinterconnected diagonal st ips, said perforated blank being formed in atube,

. tube than those which are inclined in the the strips which areinclined in one direction being at a greater angle to the axis of theopposite direction.

10. An expansion shield constructed of asheet'metal blank corrugatednear one end to form means for receiving the threads of a bolt, andperforated between said corrugated part and its other end to make aplurality of diagonal strips, said blank being rolled transversely intoa tube.

11. An expansion shield constructed of a sheet metal blank corrugatednear one end to form screw threads, and perforated between saidcorrugated part and its other end to make a plurality of oppositelyinclined interconnected diagonal strips, said blank beingrolledtransversely into a tube.

12. An expansion shield madeof a sheet metal blank with a part thereofintermediate its ends comprising portions separated by diagonallydisposed perforations, said blank being formed into a tube, saidseparated portions lying in parallel-helical lines in the tube and beingadapted to be movedtogether to decrease the size of said perforationswhen the ends of the tube are forced toward each other.

' 13.. An expansion shield comprising a tubular membercut away at spacedintervals to provide. a plurality of reversely inclined strips. Y

14. An expansion shield comprising a tubular member-of sheet metalhaving rows of perforations therein providing parallel helical strips ofmetal separated by the perforations, said member being adapted to becompressed longitudinally to bring the strips toward abutting engagementwith each other and to expand the strips laterally, inwardly andoutwardly.

An expansion shield comprising a tubular member of sheet metal havingrows of perforations therein increasing in size toward the inner end ofthe shield, providing strips of metal separated by the perforations,said member being adapted to be compressed. longitudinally to bring thestrips ERNEST W; MARSHALL.

